Assets that potentially subject the Group to a significant concentration of credit risk primarily consist of cash, accounts receivable and other current assets. The maximum exposure of such assets to credit risk is their carrying amounts as at the balance sheet dates. As of December 31, 2023 and 2024, the aggregate amount of cash of RMB 10,776 thousand and RMB4,150 thousand respectively, of these the restricted funds amount to RMB 200 thousand was held at major financial institutions in mainland PRC, where there RMB 500 thousand deposit insurance limit for a legal entity’s aggregated balance at each bank. To limit the exposure to credit risk relating to deposits, the Group primarily places cash deposits with large financial institutions in the PRC. The Group conducts credit evaluations of its customers and suppliers, and generally does not require collateral or other security from them, The Group establishes an accounting policy to provide for allowance for doubtful accounts based on the individual customer’s and supplier’s financial condition, credit history, and the current economic conditions. The Group conducts credit evaluations of its customers, and generally does not require collateral or other security from them. The Group evaluates its collection experience and long outstanding balances to determine the need for an allowance for credit losses. The Group conducts periodic reviews of the financial condition and payment practices of its customers to minimize collection risk on accounts receivable.

The following table sets forth a summary of single customers who represent 10% or more of the Group’s total accounts receivable:

The following table sets forth a summary of single customers who represent 10% or more of the Group’s total revenue.

The following table sets forth a summary of single suppliers who represent 10% or more of the Group’s total purchases: